Removable Nose Cone for Zipperless Rockets

[Launch Lug]

I by no means claim to have "invented" this method as I realize someone else may have already done this so please do not be offended if it has been posted before.

I decided to convert my Estes Vagabond rocket from the traditional deployment setup to a zipperless design. I don't like the idea of permanently "gluing" the nose cone to the upper airframe since it would most likely make it impossible to reattach a shock cord in the event that it may need to be replaced. So I set out to design a simple method for a solid attachment with the option to remove if necessary and here is what I came up with.

Step 1 - Cut end of Nose Cone off

I took a piece of card stock and wrapped it around the shoulder of the Nose Cone and drew a reference line. I then cut the bottom part of the shoulder off with my band saw and then cleaned up the edge with the disc sander.

 

[Launch Lug]

Step 2 - Cut out bulk heads

I didn't take pictures of all the next step but you should get the idea. I cut two 1/8" thick "bulk heads", one to fit inside the airframe and another to fit inside the nose cone shoulder. I stacked them and drilled out the center with a 1/2" drill as well as two holes for 6-32 blind nuts and screws. I cut a small piece of 1/2" diameter wood dowel and glued that flush in the center hole of the nose cone bulk head. I drilled a small pilot hole through the dowel to receive a screw eyelet which the shock cord will attach to. I also pressed the blind nuts into the bulkhead. After the hardware was installed I epoxied everything to make sure it will not come lose.

 

[Launch Lug]

Step 3 - Glue bulk head to Nose Cone

After scuffing up the inside of the nose cone with sandpaper I also drilled small holes around the shoulder area that will fit the bulk head. I did this so the epoxy would help lock the bulk head in place. Next I assembled the two bulk heads together and dry fit them to the nose cone and then inserted the nose cone into the airframe to make sure that everything lined up perfectly. After I was satisfied I epoxied the bulk head into the shoulder and let it set up.

 

[Launch Lug]

Step 4 - Glue bulk head to airframe

Once the nose cone portion was set up I glued the other bulk head into the airframe. I kept the two bulk heads assembled as they were from the previous step and after measuring I added glue inside the airframe. I then inserted the nose cone and bulk head assembly into the airframe and let it set up. By doing it this way it assured that the two bulk heads would be perfectly flush with one another.

First picture is looking inside the airframe after I glued the nose cone and bulk head assembly in place.
Second picture is a shot of the airframe bulk head glued in place with the nose cone removed.
Third and fourth picture is showing how the shock cord gets attached.

 

[Launch Lug]

Thank goodness for Harbor Freight and their 22" long screw driver set for $4.99, without it I couldn't have done this :headbang:



I did not weigh the additional parts to see how it would affect flight performance. Considering though I turned the tube coupler from the kit into an ejection baffle which consists of virtually the same parts (minus two 1/4" 6-32 screws, blind nuts and two #6 washers) I'm confident that it will all offset.

Hopefully this technique will be of use to others as I certainly enjoyed building it into my rocket and look forward to it's use.

 

[krusty]

Cool idea!!

Krusty